Electrically controlled brake assembly with non-cocking operating arm

Abstract

An electrically controlled brake assembly for a vehicle wheel of the type in which an operating arm is mounted between its ends to turn about a pivot on a backing plate and carries at least one electromagnet on one of its ends. Two downwardly projecting tongues are formed on the lower end of the pivoted operating arm of the brake assembly and ride in a channel defined by a guide which is attached to the backing plate of the assembly, the tongues and the guide coacting to prevent the operating arm from cocking on its pivot during braking.

I claim: 
     
       1. An electrically controlled brake assembly for use with a rotatable drum, said brake assembly comprising a stationary backing plate, a pair of brake shoes pivotally mounted on said backing plate and having ends disposed adjacent one another, an operating arm pivoted intermediate its ends on said backing plate to turn about an axis extending substantailly perpendicular to said plate and in a plane extending substantially parallel to said plate, means carried on said operating arm on one side of said axis and located between the adjacent ends of said shoes to bear against one of said shoes when said arm is turned in one direction about said axis and to bear against the other of said shoes when said arm is turned in the opposite direction about said axis, and electromagnet means carried on said operating arm on the opposite side of said axis and operable when energized to engage said drum and cause said operating arm to turn about said axis in one direction or the other depending upon the direction of rotation of said drum, the improvement in said brake assembly comprising, guide means fixed on said backing plate and located between said backing plate and said electromagnet means, said guide means and said backing plate coacting to define a channel means having an open side which faces said axis, and projecting means on said operating arm and located on circumferentially opposite sides of said electromagnet means, said projecting means extending into said channel means from the open side thereof and being engageable with said guide means and said backing plate to confine said operating arm substantially within said plane when said operating arm is turned about said axis. 
     
     
       2. An electrically controlled brake assembly as defined in claim 1 in which said projecting means comprise two projecting tongues spaced from one another and located on circumferentially opposite sides of said electromagnet means, said guide means comprising a strip secured to and spaced from said backing plate and disposed in opposing relation with said tongues. 
     
     
       3. An electrically controlled brake assembly as defined in claim 2 in which said strip is of sufficient circumferential length to be in opposing relation with said tongues throughout the entire turning stroke of said operating arm. 
     
     
       4. An electrically controlled brake assembly as defined in claim 2 in which said operating arm includes a main body portion which is disposed in said plane, said tongues being formed integrally with said main body portion and being disposed between said plane and said backing plate.